Long-term storage of radioactive material in a safe manner is an ever increasing environmental problem. Attempts have been made to have such material stored in metal barrels, but these are subject to rust or corrosion and therefore prone to leakage of the radioactive material.
To overcome such deterioration and possible leakage problem, there has been proposed to provide long-term storage containers of the type mentioned in the introductory part. Such container was essentially attempted made by inserting space members between the inner and outer container parts, and thereafter filling in liquid form the inter space with a radioactive radiation inhibiting material and leave it to solidify. However, tests proved that the inter space was not completely filled by the material, such as e.g. lead, thus leaving voids therein that would yield unacceptable radioactive radiation to the environment and cause serious health hazards to personnel handling such containers or moving about in storage rooms containing such containers filled with radioactive material. Further, such voids could only be spotted by carrying out expensive and time consuming tests, adding to the overall cost for each container, and destruction of unacceptable containers, as no means for repairs would be available
In recognition of such defective manufacturing method, and also the urgent need for safer, long-term storage containers which are ready to use after manufacturing without necessity of subsequent radioactive radiation leakage tests, the present invention provides for a method and container having properties of an inter space container part made from a void free radioactive radiation inhibiting material, and being safe and simple to manufacture, thus providing a safe, reliable storage container not requiring subsequent reliability tests.